Bake french fries according to package directions. In a small saucepan combine hot sauce, vinegar and butter on med. heat until butter is melted and well combined. When fries are done, transfer to platter and drizzle with hot sauce. Crumble blue cheese all over fries and pop back in the oven for a second so the cheese can melt just slightly and stick to the fries. Serve with Ranch dressing for dipping if desired.